It All Changed in the ’80s

No, this is not another boomer screed about how great the ’60s were. In fact it’s a remarkable story about preserving records; astronomical, historically valuable records. I try not to give the NYT links, because their credibility is lacking, in their science articles as much as in their political. But the linked story is very good.

[O]n Observatory Hill, just up Garden Street from Harvard Square: more than half a million images constituting humanity’s only record of a century’s worth of sky.

“Besides being 25 percent of the world’s total of astronomical photographic plates, this is the only collection that covers both hemispheres,” said Alison Doane, curator of a glass database occupying three floors, two of them subterranean, connected by corkscrew stairs. It weighs 165 tons and contains more than a petabyte of data. The scary thing is that there is no backup.

From about 1889, for decades, a young astronomer named Solon I. Bailey sent tens of thousands of photographic plates, the very first of “astronomical quality” from Peru to Harvard College Observatory, where they remain as an amazing record of the sky (and the only one of both hemispheres) for that century. Indeed, the whole collection of plates taken from many locations (including Harvard) contains a century’s worth of data and is on about half a million glass plates. The collection of data continued that way until about 1980, when almost overnight, charged couple devices (CCDs) became the mainstay of astronomical data collection. The reality was that the data went almost directly into the computer, then to storage, and glass was, well, antiquated.

But what do you do with 165 tons of glass plates in the 21st century? You scan it into a computer, right? Well, in the ’80s and ’90s, even the highest of high end scanners could handle one of those plates in about 10 minutes. If you do the math, you’ll see that half a million plates (100 years worth of data), scanned for about 8 working hours a day, would be totally digitized in about, oh, 50 years. This is not what you call cost efficient. The time is down to about a decade now, using custom built scanners and tons of time donated by amateurs.

And that’s where my personal experience enters this picture. Sigh – had I only known. About that same time I was at the Space Telescope Science Institute (STScI) in Baltimore, working as a contractor, on the HST. What I did (as a young worker-bee, only a few years out of grad-school) was, you guessed it, scanned glass plates to identify guide stars for HST. They were substantially newer, highly uniform plates from Palomar, but the game was still to optimize, optimize and optimize some more so that the launch schedule could be met.

The schedule got “relaxed” when the Challenger exploded. But by that time, I wish I had known to apply to Harvard to see if they needed anybody with my particular experience. It would have been… interesting.

Explore posts in the same categories: Astronomy

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